Abstract
Introduction: Glucocorticoids are commonly prescribed medications associated with significant mortality and morbidity, even when used at physiological dosages. The endogenous glucocorticoids are secreted in a complex rhythm consisting of both a daily circadian rhythm and a more rapid and dynamic ultradian rhythm that is highly conserved in nature. Current therapeutic options attempt to target the circadian aspects of this rhythm but do not take into account the oscillating ultradian pulsatility.
Areas covered: This article analyzes English-language literature on Pubmed and discusses the physiology and evidence behind the importance of different patterns of glucocorticoid presentation on gene regulation, animal responses and clinical significance.
Expert opinion: There is compelling evidence for pulsatility being an important factor in hypothalamic pituitary adrenal (HPA) axis regulation and tissue responses to glucocorticoids. Different patterns of gene regulation and neural and behavioral responses are seen dependent upon the pattern of glucocorticoid presentation. Disease states are associated with disordered HPA ultradian activity. Glucocorticoid treatments have significant risk/benefit issues. It is now time to go back to first principles and think about the physiology and patterns of drug presentation in glucocorticoid-based therapeutics.
Notes
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